Centertonix is the Cotuit Center for the Arts' a cappella group. This exciting ensemble includes a variety of ages and vocal talents, and is prepared to entertain you with jazz, show tunes, pop, and doo-wop numbers. Their beautiful sound will be sure to delight.

Under the musical direction of Steve Stein, the group began meeting in March 2107. They debuted at the Cotuit Center’s Derby Day Celebration two months later.

Today Centertonix presents a cappella harmony from a wide range of styles and eras. This is a group of talented a cappella singers whose mission is to entertain with an inspiring sound and to educate audiences about the wide variety of a cappella genres.

The group is available to share with you their love of harmony and knowledge of a cappella history. Their excitement, energy, and talent can be hired for your speakers’ series, private party, retirement community, outdoor venue, and organization’s activity.

Please contact Centertonix artist manager Idell Stein at for information.

Rehearsals are Tuesday evenings from 7-9PM. Auditions are ongoing with admittance based upon the talent of the auditionee and the specific vocal needs of the group.

Meet the Group

Rob Anderson learned to sing in church choirs in Worcester and Wilbraham. A “knee-knocking” choir solo as a 10 year old at the First Baptist Church, Worcester set off a love of singing. Fellow Centertonix member Ben Ayres and Rob sang together many years ago in that boys’ choir. Rob is a Master Gardener with the Barnstable County Extension Service and a ‘semi-retired' attorney/farmer. Rob’s business card states, “Attorney at Farm.” Rob jokes that he honed his singing talents after rugby matches at Colby College.

Ben Ayres was in the glee club of Pomfret School where the highlight each year was a performance in Hartford, with several other schools, of such works as Carmina Burana. Also at Pomfret, Ben was Benny in Guys and Dolls. Ben sang in the Dartmouth Glee Club during his college years, and with church choirs in Worcester and Pennsylvania. He was an English and journalism teacher and school librarian before retirement. He and his wife, Amanda, have two grown sons and a Newfoundland mix who loves to walk them on the beach.

Frank Callahan has enjoyed singing all his life. He has sung with many theater groups, barbershop and gospel choirs, and chorales including the Good News Gospel Choir, the Coastal Chordsmen, and the Fairfield County Chorale in Connecticut. While a Marist Brother, he even sang Gregorian chant. Frank lives in Brewster and leads group exercise classes at the Barnstable YMCA.

Aimee Champagne is a student in Sandwich public schools. Aimee has performed in school plays and musicals for a few years. She has also performed in shows at the Cotuit Center for the Arts. Aimee started singing from an early age in church. This is her first experience with a cappella music. She is so grateful to be part of such a talented group.

Kristina Donnellan started her musical path at a very early age, singing canons and harmonizing with her mother and brothers to pass the time during long family car rides. A strong love for singing was born, and she has since sung in numerous choruses, church choirs, duos and ensembles, both in her native country Sweden and in the US. In the late 1990’s, she had the exciting opportunity to perform on tour with the Boston Pops while singing with the William Hall Master Chorale in Southern California. More recent experience includes singing with the Cranberry Shores Chorus and the Cape Cod Conservatory Jazz Ensemble.

Treather Gassmann received her undergraduate degree in Vocal Performance from the Boston Conservatory and then her master’s degree in Theatre Education from Emerson College. Treather is a diverse educator with experience directing youth theatre and teaching special and general education students. When she is not teaching she is on stage singing and/or acting. Most recently, she has taken up playing the ukulele. Treather is very excited to join Centertonix and is looking forward to learning and performing with this talented group!

Liesl Keller teaches choral music at Mashpee Middle and High School and is working toward her Master's degree in Choral Conducting. In recent years she has enjoyed performing rock music with the band "Second Nature," folk music with Lorre Wyatt, and choral music with several ensembles. This is her first experience singing in a contemporary a cappella group.

Janet Leahy grew up singing in church choirs and chamber music ensembles in high school, and received a vocal scholarship to college. Since moving to Cape Cod, she has been active in several vocal and musical theater groups, including a mid-Cape madrigal group and Eventide Arts. She's also has extensive experience teaching music to children, and singing for the elderly. Most recently, Janet appeared in Scrooge-The Musical and Elegies For Angels, Punks and Raging Queens here at the CCftA.

Liam Mahony is the former director of “Half Step Down,” the a cappella ensemble of Sturgis Charter Public School East in Hyannis, a group he started with his son five years ago. Earlier in life, he studied classical piano in college, and sang in several choirs, including Boston’s Back Bay Chorale. After a long break from singing, Liam is thrilled to have the opportunity to sing a cappella with Centertonix. Liam most recently performed as an Apostle in CCFTA's production of Jesus Christ Superstar.

Brandon Prentiss: In winter 2018 Brandon became the newest member of Centertonix. Some recent projects of his include”1940’s Radio Hour” at Barnstable Comedy Club, “Of Mice and Men”, “Man of La Mancha”, a Black Box production of an original play by Jim Dalglish “Dark Tales Told on a Cold Autumn Eve” at the Cotuit Center for The Arts and “Fun Home” at the Falmouth Theater Guild. Brandon found his passion for the craft as a cast member in the North Cambridge family opera Company and as a soloist/ensemble performer. He studied Improv in college and for the last few years he has acted in numerous independent/student films. He has also done solo work in many different chorus groups (Mystic Chorale, Centertonix etc.).

John Quesnel grew up singing around his mother’s piano, starting at age 3. He sang with, and was the emcee for the Narragansett Bay Chorus in Providence for 20 years, winning the Northeastern District Barbershop championship and going on to compete in International competitions in 11 of those years. He has sung in many quartets, most notably the “P’s & Q’s” with his wife Linda and another couple, who for 10 years entertained audiences from Maine to Florida. In his previous life John was an actuary and principal in a pension consulting firm. In addition to singing he loves to play golf, although he finds golf much more difficult!

Linda Quesnel is fortunate to have been born into a music-loving family. Everyone played at least one instrument, and singing harmony was part of every family gathering and car trip. She was especially drawn to a cappella singing and started singing formally in church and school. At the age of 30 she discovered a woman’s barbershop chorus and since that time has sung in 6 competitive choruses, one of which was an International top 10 finalist. Linda sang lead in “Jazz Reunion”, a regional quartet champion and International competitor. She and her husband John sang in the medal-winning mixed a cappella quartet, “P’s & Q’s”, for 10 years. Linda is a retired Marriage & Family Therapist and finds singing to be her personal therapy. John and Linda have 5 children and 8 grandchildren.

Steve Stein, musical director, has nearly 50 years of a cappella group experiences, from his high school barbershop quartet, to singing with and directing the MIT Logarhythms, to singing with the Cape Cod Surftones and the quartet “Take the Fifth”. In his years of choral singing, he has sung with the Tanglewood Festival Chorus, the New World Chorale and Chorus Pro Musica. He has also appeared in many musical theater productions including Scrooge and Pirates of Penzance at CCftA and most recently as Counsel for the Plaintiff in Eventide's production of Trial by Jury.